Japan-based Daiichi Sankyo has signed an agreement to acquire US-based Ambit Biosciences, for about $410m.
As part of the deal, Daiichi will pay $15 per share in cash to Ambit through a tender offer, and will merge it with a subsidiary of the company, or $315m on a fully diluted basis.
Ambit's stock holders will also have a right to receive an additional cash payment of up to $4.50 for each share upon achieving certain commercialisation related milestones.
Ambit Biosciences president and CEO Michael Martino said: "Daiichi Sankyo is the ideal organisation to take quizartinib to the next stage of development, and ultimately, to achieve our goal of making it available as quickly as possible to help as many AML patients as possible."
Ambit Biosciences develops medicines to treat unmet medical needs in oncology, autoimmune and inflammatory diseases.
Currently, the company is carrying Phase III clinical trials for its drug candidate, quizartinib, among patients with acute myeloid leukaemia (AML).
Daiichi Sankyo president and CEO Joji Nakayama said: "The acquisition of Ambit Biosciences further builds our presence in oncology to ensure we are delivering on our goal of providing world-class, innovative pharmaceuticals in core areas of unmet medical need.
"Long-term success in oncology depends upon three pillars: fostering development of our in-house molecules, exploring mutually beneficial partnerships and executing strategic purchases, such as Ambit Biosciences, which follows our acquisitions of U3 Pharma and Plexxikon."
Centerview Partners and Leerink Partners have served as financial advisors to Ambit Biosciences, while Cooley acted as legal advisor. Simpson Thacher & Bartlett served as legal advisor to Daiichi Sankyo.